Re: Paragraph indentation suppression

[Simon Law]

I have made some of the changes suggested by Stepan.  Since he didn't
actually write any code *grin* some of his suggestions completely failed
to work.  But that's OK.

        His idea of putting the \suppressfirstparagraphindent command in
only \sectionheading failed.  \sectionheading isn't called for all
instances we want.

        His idea for simplifying \everypar worked wonderfully.

        His idea for removing the extra \gobble* commands seems to be
fine.  I have not been able to break anything with this modification,
so I presume it was extraneous.

        I include a new changelog and a new patch.  This one should be
ready to commit, barring any objections.

Simon

2003-04-12  Simon Law  <address@hidden>

        * doc/texinfo.tex (\firstparagraphindent): implement suppression
        of the indentation of the first paragraph.
        (\dofirstparagraphindent): for parsing arguments.
        (\suppressfirstparagraphindent): does the actual gobbling of 
        indentation.
        (\footnote): Compensate for the hanging-indent side-effect.
        (\numhead, \apphead, \unnmhead): ensures the suppression occurs.
        * makeinfo/cmds.c (command_table): add "firstparagraphindent"
        (as cm_firstparagraphindent)
        (set_firstparagraphindent, cm_firstparagraphindent): implement
        @firstparagraphindent parsing of options.
        * makeinfo/makeinfo.c (long_options): add "no-first-par-indent"
        (as &no_first_par_indent).
        * makeinfo/makeinfo.h: declare "no_first_par_indent".
        * makeinfo/sectioning.c (sectioning_underscore): suppress
        indentation.
        * doc/texinfo.txi: document it.

        * doc/texinfo.tex (\indent): override \indent primitive to
        clear \everypar.
        (\ptexindent): for saving/restoring \indent in @tex.
        (\footnote, \dofootnote): Neutralise the effect of @indent
        within a footnote.
        * makeinfo/cmds.c (command_table): add "indent" (as cm_indent).
        (cm_indent): un-inhibit_paragraph_indentation.
        * doc/texinfo.txi: document it.

        * doc/texinfo.txi: take advantage of @firstparagraphindent.

        * doc/texinfo.txi (Conventions): remove extra vertical space
        from bulleted itemize.

        * makeinfo/cmds.c (command_table): fix "novalidate" option.

Index: doc/texinfo.tex
===================================================================
RCS file: /cvsroot/texinfo/texinfo/doc/texinfo.tex,v
retrieving revision 1.67
diff -u -r1.67 texinfo.tex
--- doc/texinfo.tex     22 Mar 2003 16:50:15 -0000      1.67
+++ doc/texinfo.tex     12 Apr 2003 20:57:55 -0000
@@ -3,7 +3,7 @@
 % Load plain if necessary, i.e., if running under initex.
 \expandafter\ifx\csname fmtname\endcsname\relax\input plain\fi
 %
-\def\texinfoversion{2003-03-22.08}
+\def\texinfoversion{2003-04-12.17}
 %
 % Copyright (C) 1985, 1986, 1988, 1990, 1991, 1992, 1993, 1994, 1995,
 % 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
@@ -88,6 +88,7 @@
 \let\ptexgtr=>
 \let\ptexhat=^
 \let\ptexi=\i
+\let\ptexindent=\indent
 \let\ptexlbrace=\{
 \let\ptexless=<
 \let\ptexplus=+
@@ -866,6 +867,34 @@
   \parindent = \defaultparindent
 }
 
+% @firstparagraphindent NCHARS
+% We'll use ems for NCHARS like @paragraphindent.
+\let\suppressfirstparagraphindent=\relax
+\newdimen\currentparindent
+\def\suppressword{suppress}
+\def\defaultword{default}
+\def\firstparagraphindent{\parsearg\dofirstparagraphindent}
+\def\dofirstparagraphindent#1{%
+  \def\temp{#1}%
+  \ifx\temp\suppressword
+    \gdef\suppressfirstparagraphindent{%
+      \gdef\indent{%
+        \global\everypar = {}%
+        \global\let\indent=\ptexindent
+      }%
+      \global\everypar = {%
+        \kern-\parindent
+        \global\let\indent=\ptexindent
+        \global\everypar = {}
+      }%
+    }%
+  \else\ifx\temp\defaultword
+  \else
+    \errhelp = \EMsimple
+    \errmessage{Unknown @firstparagraphindent `\temp'}%
+  \fi\fi
+}
+
 % @exampleindent NCHARS
 % We'll use ems for NCHARS like @paragraphindent.
 % It seems @exampleindent asis isn't necessary, but
@@ -3721,6 +3750,7 @@
     \numberedsubsubseczzz{#2}
   \fi
 \fi
+\suppressfirstparagraphindent
 }
 
 % like \numhead, but chooses appendix heading levels
@@ -3740,6 +3770,7 @@
     \appendixsubsubseczzz{#2}
   \fi
 \fi
+\suppressfirstparagraphindent
 }
 
 % like \numhead, but chooses numberless heading levels
@@ -3759,6 +3790,7 @@
     \unnumberedsubsubseczzz{#2}
   \fi
 \fi
+\suppressfirstparagraphindent
 }
 
 % @chapter, @appendix, @unnumbered.
@@ -4430,6 +4462,7 @@
   \let\equiv=\ptexequiv
   \let\!=\ptexexclam
   \let\i=\ptexi
+  \let\indent=\ptexindent
   \let\{=\ptexlbrace
   \let\+=\tabalign
   \let\}=\ptexrbrace
@@ -6146,6 +6179,7 @@
 %
 % Auto-number footnotes.  Otherwise like plain.
 \gdef\footnote{%
+  \let\indent=\relax
   \global\advance\footnoteno by address@hidden
   \edef\thisfootno{$^{\the\footnoteno}$}%
   %
@@ -6177,6 +6211,7 @@
   % We want to typeset this text as a normal paragraph, even if the
   % footnote reference occurs in (for example) a display environment.
   % So reset some parameters.
+  \ptexindent
   \hsize=\pagewidth
   \interlinepenalty\interfootnotelinepenalty
   \splittopskip\ht\strutbox % top baseline for broken footnotes
Index: doc/texinfo.txi
===================================================================
RCS file: /cvsroot/texinfo/texinfo/doc/texinfo.txi,v
retrieving revision 1.37
diff -u -r1.37 texinfo.txi
--- doc/texinfo.txi     9 Apr 2003 12:29:26 -0000       1.37
+++ doc/texinfo.txi     12 Apr 2003 20:58:03 -0000
@@ -29,6 +29,7 @@
 
 @footnotestyle separate
 @paragraphindent 2
address@hidden suppress
 @c finalout
 
 @comment %**end of header
@@ -257,6 +258,7 @@
 * documentdescription::         Document summary for the HTML output.
 * setchapternewpage::           Start chapters on right-hand pages.
 * paragraphindent::             Specify paragraph indentation.
+* firstparagraphindent::        Suppress indentation of the first paragraph.
 * exampleindent::               Specify environment indentation.
 
 Ending a Texinfo File
@@ -372,6 +374,7 @@
 * exdent::                      Undo indentation on a line.
 * flushleft & flushright::      Pushing text flush left or flush right.
 * noindent::                    Preventing paragraph indentation.
+* indent::                      Forcing paragraph indentation.
 * cartouche::                   Drawing rounded rectangles around examples.
 
 Lists and Tables
@@ -1245,6 +1248,9 @@
 @xref{Conditionals}.
 
 @item
address@hidden
address@hidden@baselineskip
address@hidden iftex
 @cindex Tabs; don't use!
 @quotation
 @strong{Caution:} Do not use tab characters in a Texinfo file (except in
@@ -3668,6 +3674,7 @@
 * documentdescription::         Document summary for the HTML output.
 * setchapternewpage::           Start chapters on right-hand pages.
 * paragraphindent::             Specify paragraph indentation.
+* firstparagraphindent::        Suppress indentation of the first paragraph.
 * exampleindent::               Specify environment indentation.
 @end menu
 
@@ -3779,7 +3786,7 @@
 
 
 @node paragraphindent
address@hidden Paragraph Indenting
address@hidden @code{@@paragraphindent}: Paragraph Indenting
 @cindex Indenting paragraphs, control of
 @cindex Paragraph indentation control
 @findex paragraphindent
@@ -3824,6 +3831,50 @@
 @xref{Refilling Paragraphs}, for further information.
 
 
address@hidden firstparagraphindent
address@hidden @code{@@firstparagraphindent}: Suppress Indentation of the First 
Paragraph
address@hidden First paragraph, suppressing indentation of
address@hidden Suppressing first paragraph indentation
address@hidden Preventing first paragraph indentation
address@hidden Indenting, suppressing of first paragraph
address@hidden firstparagraphindent
+
+As you can see, the first paragraph in any section is never indented.
+Indentation is meant to be a paragraph separator, which means that it
+is unnecessary when a new section begins.  In fact, it is a typographical
+error to indent the first paragraph.
+
+In order to preserve compatibility with older versions of Texinfo,
+the default behaviour is to indent the first paragraph.  However, the
address@hidden option is recommended.
+
address@hidden
+@@firstparagraphindent @var{indent}
address@hidden example
+
+The first paragraph is indented according to the value of @var{indent}:
+
address@hidden @asis
address@hidden @code{suppress}
+Prevents the first paragraph from being indented.  This option is
+ignored if @code{@@paragraphindent asis} is in effect.
+
address@hidden @code{default}
+Leaves the indentation as-is.  By default, this will respect the
+Paragraph Indentation set by an @code{@@paragraphindent} command.
+(@pxref{paragraphindent})
+
address@hidden table
+
+Like @code{@@paragraphindent}, the default value of @var{indent} 
+is @code{default}.  In HTML output, the value of 
address@hidden@@firstparagraphinput} is ignored.
+
+Similiarily, it is best to write the @code{@@firstparagraphindent}
+command before the end-of-header line at the beginning of a Texinfo
+file.  @xref{Start of Header}.
+
+
 @node exampleindent
 @subsection @code{@@exampleindent}: Environment Indenting
 @cindex Indenting environments
@@ -7522,6 +7573,7 @@
 * exdent::                      Undo indentation on a line.
 * flushleft & flushright::      Pushing text flush left or flush right.
 * noindent::                    Preventing paragraph indentation.
+* indent::                      Forcing paragraph indentation.
 * cartouche::                   Drawing rounded rectangles around examples.
 @end menu
 
@@ -8019,6 +8071,9 @@
 
 @node noindent
 @section @code{@@noindent}: Omitting Indentation
address@hidden Omitting indentation
address@hidden Suppressing indentation
address@hidden Indentation, omitting
 @findex noindent
 
 An example or other inclusion can break a paragraph into segments.
@@ -8078,6 +8133,32 @@
 paragraphs (@pxref{Command Syntax}).
 
 
address@hidden indent
address@hidden @code{@@indent}: Forcing Indentation.
address@hidden Forcing indentation
address@hidden Inserting indentation
address@hidden Indentation, forcing
address@hidden indent
+
address@hidden
+To complement the @code{@@noindent} command (@pxref{noindent}), Texinfo
+provides the @code{@@indent} command that forces a paragraph to be
+indented.  This paragraph is indented using an @code{@@indent} command.
+
+It is best to write @code{@@indent} on a line by itself, since in most
+environments, spaces following the command will not be ignored.  It's ok
+to use it at the beginning of a line, with text following, outside of
+any environment.
+
+To adjust the number of blank lines properly in the Info file output,
+remember that the line containing @code{@@indent} does not generate a
+blank line, and neither does the @code{@@end example} line.
+
+Do not put braces after an @code{@@indent} command; they are not
+necessary, since @code{@@indent} is a command used outside of
+paragraphs (@pxref{Command Syntax}).
+
+
 @node cartouche
 @section @code{@@cartouche}: Rounded Rectangles Around Examples
 @findex cartouche
@@ -14223,6 +14304,12 @@
 @code{makeinfo} and then discarded.  This option is used by
 @command{texi2dvi} if you are using an old version of @file{texinfo.tex}
 that does not support @code{@@macro}.
+
address@hidden --no-first-par-indent
address@hidden --no-first-par-indent
+Never indents the first paragraph of any section.  This option overrides 
+the value set in a Texinfo file by an
address@hidden@@firstparagraphindent} command (@pxref{firstparagraphindent}).  
 
 @item --no-headers
 @opindex --no-headers
Index: makeinfo/cmds.c
===================================================================
RCS file: /cvsroot/texinfo/texinfo/makeinfo/cmds.c,v
retrieving revision 1.17
diff -u -r1.17 cmds.c
--- makeinfo/cmds.c     7 Mar 2003 19:22:52 -0000       1.17
+++ makeinfo/cmds.c     12 Apr 2003 20:58:03 -0000
@@ -56,7 +56,8 @@
   cm_anchor (), cm_node (), cm_menu (), cm_xref (), cm_ftable (),
   cm_vtable (), cm_pxref (), cm_inforef (), cm_uref (), cm_email (),
   cm_quotation (), cm_display (), cm_smalldisplay (), cm_itemize (),
-  cm_enumerate (), cm_tab (), cm_table (), cm_itemx (), cm_noindent (),
+  cm_enumerate (), cm_tab (), cm_table (), cm_itemx (), 
+  cm_noindent (), cm_indent (),
   cm_setfilename (), cm_br (), cm_sp (), cm_page (), cm_group (),
   cm_center (), cm_ref (), cm_include (), cm_bye (), cm_item (), cm_end (),
   cm_kindex (), cm_cindex (), cm_findex (), cm_pindex (), cm_vindex (),
@@ -66,7 +67,8 @@
   cm_defcodeindex (), cm_result (), cm_expansion (), cm_equiv (),
   cm_print (), cm_error (), cm_point (), cm_today (), cm_flushleft (),
   cm_flushright (), cm_finalout (), cm_cartouche (), cm_detailmenu (),
-  cm_multitable (), cm_settitle (), cm_titlefont (), cm_titlepage (), cm_tie 
(), cm_tt (),
+  cm_multitable (), cm_settitle (), cm_titlefont (), cm_titlepage (), 
+  cm_tie (), cm_tt (),
   cm_verbatim (), cm_verbatiminclude ();
 
 /* Conditionals. */
@@ -74,7 +76,10 @@
 void cm_value (), cm_ifeq ();
 
 /* Options. */
-static void cm_paragraphindent (), cm_exampleindent ();
+static void 
+  cm_paragraphindent (),
+  cm_firstparagraphindent (),
+  cm_exampleindent ();
 
 /* Internals. */
 static void cm_obsolete ();
@@ -220,6 +225,7 @@
   { "file", cm_code, BRACE_ARGS },
   { "finalout", cm_no_op, NO_BRACE_ARGS },
   { "findex", cm_findex, NO_BRACE_ARGS },
+  { "firstparagraphindent", cm_firstparagraphindent, NO_BRACE_ARGS },
   { "flushleft", cm_flushleft, NO_BRACE_ARGS },
   { "flushright", cm_flushright, NO_BRACE_ARGS },
   { "footnote", cm_footnote, NO_BRACE_ARGS}, /* self-arg eater */
@@ -248,6 +254,7 @@
   { "ignore", command_name_condition, NO_BRACE_ARGS },
   { "image", cm_image, BRACE_ARGS },
   { "include", cm_include, NO_BRACE_ARGS },
+  { "indent", cm_indent, NO_BRACE_ARGS },
   { "inforef", cm_inforef, BRACE_ARGS },
   { "insertcopying", cm_insert_copying, NO_BRACE_ARGS },
   { "item", cm_item, NO_BRACE_ARGS },
@@ -269,7 +276,7 @@
   { "need", cm_ignore_line, NO_BRACE_ARGS },
   { "node", cm_node, NO_BRACE_ARGS },
   { "noindent", cm_noindent, NO_BRACE_ARGS },
-  { "noindent", cm_novalidate, NO_BRACE_ARGS },
+  { "novalidate", cm_novalidate, NO_BRACE_ARGS },
   { "nwnode", cm_node, NO_BRACE_ARGS },
   { "o", cm_special_char, BRACE_ARGS },
   { "oddfooting", cm_ignore_line, NO_BRACE_ARGS },
@@ -995,6 +1002,13 @@
     inhibit_paragraph_indentation = -1;
 }
 
+/* This says to indentation the next paragraph. */
+void
+cm_indent ()
+{
+  inhibit_paragraph_indentation = 0;
+}
+
 /* I don't know exactly what to do with this.  Should I allow
    someone to switch filenames in the middle of output?  Since the
    file could be partially written, this doesn't seem to make sense.
@@ -1398,6 +1412,33 @@
 
   get_rest_of_line (1, &arg);
   if (set_paragraph_indent (arg) != 0)
+    line_error (_("Bad argument to %c%s"), COMMAND_PREFIX, command);
+
+  free (arg);
+}
+
+/* @firstparagraphindent: suppress indentation in the first paragraph. */
+static int
+set_firstparagraphindent (string)
+     char *string;
+{
+  if (strcmp (string, "default") == 0 || strcmp (string, _("default")) == 0)
+    ;
+  else if (strcmp (string, "suppress") == 0 
+           || strcmp (string, _("suppress")) == 0)
+    no_first_par_indent = 1;
+  else
+    return -1;
+  return 0;
+}
+
+static void
+cm_firstparagraphindent ()
+{
+  char *arg;
+
+  get_rest_of_line (1, &arg);
+  if (set_firstparagraphindent (arg) != 0)
     line_error (_("Bad argument to %c%s"), COMMAND_PREFIX, command);
 
   free (arg);
Index: makeinfo/makeinfo.c
===================================================================
RCS file: /cvsroot/texinfo/texinfo/makeinfo/makeinfo.c,v
retrieving revision 1.24
diff -u -r1.24 makeinfo.c
--- makeinfo/makeinfo.c 8 Apr 2003 14:13:54 -0000       1.24
+++ makeinfo/makeinfo.c 12 Apr 2003 20:58:05 -0000
@@ -427,6 +427,7 @@
       --paragraph-indent=VAL  indent Info paragraphs by VAL spaces (default 
%d).\n\
                                 If VAL is `none', do not indent; if VAL is\n\
                                 `asis', preserve existing indentation.\n\
+      --no-first-par-indent   suppress indentation of the first paragraph.\n\
       --split-size=NUM        split Info files at size NUM (default %d).\n"),
              fill_column, paragraph_start_indent,
              DEFAULT_SPLIT_SIZE);
@@ -503,6 +504,7 @@
   { "iftex", 0, &process_tex, 1 },
   { "ifxml", 0, &process_xml, 1 },
   { "macro-expand", 1, 0, 'E' },
+  { "no-first-par-indent", 0, &no_first_par_indent, 1 },
   { "no-headers", 0, &no_headers, 1 },
   { "no-ifhtml", 0, &process_html, 0 },
   { "no-ifinfo", 0, &process_info, 0 },
Index: makeinfo/makeinfo.h
===================================================================
RCS file: /cvsroot/texinfo/texinfo/makeinfo/makeinfo.h,v
retrieving revision 1.5
diff -u -r1.5 makeinfo.h
--- makeinfo/makeinfo.h 5 Apr 2003 22:51:01 -0000       1.5
+++ makeinfo/makeinfo.h 12 Apr 2003 20:58:05 -0000
@@ -178,6 +178,10 @@
    is, generate plain text.  (--no-headers) */
 DECLARE (int, no_headers, 0);
 
+/* Nonzero means that we suppress the indentation of the first paragraph
+   in any section.  (--no-first-par-indent) */
+DECLARE (int, no_first_par_indent, 0);
+
 /* Nonzero means that we process @html and @rawhtml even when not
    generating HTML.  (--ifhtml) */
 DECLARE (int, process_html, 0);
Index: makeinfo/sectioning.c
===================================================================
RCS file: /cvsroot/texinfo/texinfo/makeinfo/sectioning.c,v
retrieving revision 1.8
diff -u -r1.8 sectioning.c
--- makeinfo/sectioning.c       22 Mar 2003 17:40:54 -0000      1.8
+++ makeinfo/sectioning.c       12 Apr 2003 20:58:05 -0000
@@ -215,6 +215,11 @@
 sectioning_underscore (cmd)
      char *cmd;
 {
+  /* If we're not indenting the first paragraph, we shall make it behave
+     like @noindent is called directly after the section heading. */
+  if (no_first_par_indent)
+    cm_noindent ();
+
   if (xml)
     {
       char *temp;